So you think you're so clever never in doubt
But I've seen you two together fooling about
Don't get me wrong now I've seen what you are
Mummy wouldn't like it, it's gone too far
Got to - keep it in the family
Learn to - keep it in the family
Have to - keep it in the family
Want to - keep it in the family
Playing with each other its your favourite game
You never try to hide it there's no shame
You'll soon be discovered what will you do then
Family entertainment will come to an end
Got to